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Title: Intercalation of Polyacrylonitrile Nanoparticles in Ti 3 C 2 T x MXene Layers for Improved Supercapacitance
We report the intercalation of polyacrylonitrile nanoparticles in Ti3C2Tx MXene layers through simple sonication. The use of polyacrylonitrile, which was synthesized via radical polymerization, offered dual benefits: (1) It increased the interlayer spacing of MXene, thereby exposing more surface area and enhancing ion transport channels during charge and discharge cycles, and (2) Integrating MXene with polyacrylonitrile enables the creation of a composite with conductive properties, following percolation principle. X-ray diffraction analysis showed an increase in the c-lattice parameter, indicative of the interlayer spacing, from 22.31 Å for the pristine MXene to 37.73 Å for the MXene−polyacrylonitrile composite. The intercalated polyacrylonitrile nanoparticles facilitated the delamination by weakening the interlayer interactions, especially during sonication. Electrochemical assessments revealed significant improvement in the properties of the MXene−polyacrylonitrile composite compared to the pristine MXene. The assembled asymmetric device achieved a good specific capacitance of 32.1 F/g, an energy density of 11.42 W h/kg, and 82.2% capacitance retention after 10,000 cycles, highlighting the practical potential of the MXene−polyacrylonitrile composite.  more » « less
Award ID(s):
1800795
PAR ID:
10562233
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Applied Materials & Interfaces
Volume:
16
Issue:
47
ISSN:
1944-8244
Page Range / eLocation ID:
64784 to 64796
Subject(s) / Keyword(s):
MXenes polymer nanocomposites supercapacitor energy storage
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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